Field of the Invention
The present invention relates to an image display device, an image display system, and control methods therefor.
Description of the Related Art
Conventionally, in an image display device including a liquid crystal panel, partial disorder of liquid-crystal molecular orientation is sometimes caused by stress of a member supporting the liquid crystal panel, or the like. The disorder of the liquid-crystal molecular orientation cannot fully reduce transmissivity of light through the liquid crystal molecules, when low-gradation image data is input. Thus, transmittance in the liquid crystal panel is uneven, and when a low-gradation image is displayed, partial bright area may be generated (referred to as uneven black display in the present specification).
A technology for correction of the uneven black display is disclosed in International Publication No. 2011/121630. In the technology, a signal obtained by adding a correction value to input signal gradation is input to a liquid crystal panel to align liquid crystal molecules, for correction of the uneven black display.